Areall martians? This is what seems to be deduced from a new discovery made by Steven Benner, from the Westheimer Institute for Science and Technology (USA). At a conference held today in Florence, Italy, the Annual Conference of the European Geochemical Association, Benner will tell the assembled geochemists that uAn oxidized mineral form of the chemical element molybdenum, which was almost certainly crucial to the origin of life, may have been available only on the surface of Marsand not on Earth.
“This form of molybdenum should not have been available on Earth at the time that life began, because3,000 million years ago the Earth’s surface had very little oxygen“explained Benner, who assures that the element could be available on Mars on that date.” This makes it more likely thatlife came to Earth in a Martian meteoriterather than starting on our own planet, “he adds.
Professor Benner’s research focuses on two paradoxes that make it difficult to understand how life could have started on Earth. The first, baptized by this expert as “tar paradox”, is that all living beings are made of organic matter, but if energy such as heat or light is added to organic molecules and left in their air, far from creating life they turn into something more like tar, oil, or asphalt.
“Certain elements seem to be able to control the propensity of organic materials to turn into tar, especially boron and molybdenum, so we believe that both minerals were essential for life to begin”, explains Professor Benner, recalling that Analysis of a Martian meteorite recently showed that there was boron on Mars. “Now we believe that the oxidized form of molybdenum was also there,” emphasizes the researcher.
The second paradox is thatlife would have had serious difficulties to start on the primitive Earth as it was completely covered by water, which would prevent the accumulation of sufficient concentrations of boron, an element currently only found in very dry places like Death Valley. Added to this is that water corrodes RNA, which scientists believe was the first genetic molecule to appear. However, if the scene was the red planet, although there was water there too, it covered much smaller areas than on the early Earth.
“The evidence seems to indicate that in reality we are all Martians, that life began on Mars and came to Earth on a rock,” Benner says, adding thatit is fortunate that life reached the blue planet because it is “the best of the two to sustain life”.
